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1.
J Chromatogr A ; 1700: 464046, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37167804

RESUMO

To solve the problems of unstable adsorption performance and high organic solvent consumption of traditional molecular imprinting materials, we developed a water-resistant and highly adsorptive molecularly imprinted sulfamethazine polymer (MIP) through a novel synthetic strategy consisting of the application of mixed functional monomers combined with hydrophobic crosslinkers. The results showed that the imprinting factor of the prepared MIP was increased from 0.93 to 4.38, and that the relative selection coefficient k' was 5.59. With the application of the material to be developed as a solid-phase extraction (SPE) filler for sulfonamides (SAs) in milk combined with UPLC-MS/MS, the validated method showed a sensitive quantification limit (0.89 µg/kg), a steady recovery (95.55%-97.97%) and an excellent precision (0.08%-2.92% RSD). Moreover, after 5 times usage, the recovery rate of MIP-SPE was still above 90%. Therefore, the prepared materials showed high performance of molecular adsorption and were water-resistant, which was also considered an excellent filler of SPE for SAs extraction in food or other fields.


Assuntos
Impressão Molecular , Polímeros Molecularmente Impressos , Animais , Polímeros/química , Espectrometria de Massas em Tandem , Leite/química , Cromatografia Líquida , Água/química , Sulfonamidas/análise , Extração em Fase Sólida/métodos , Impressão Molecular/métodos , Adsorção , Cromatografia Líquida de Alta Pressão/métodos
2.
Cogn Neurodyn ; 16(4): 887-897, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35847534

RESUMO

The influences of chaotic activity and time delay on the transmission of the sub-threshold signal (STS) in a single FitzHugh-Nagumo neuron and coupled neuronal networks are studied. It is found that a moderate chaotic activity level can enhance the system's detection and transmission of STS. This phenomenon is known as chaotic resonance (CR). In a single neuron, the large amplitude and small period of the STS have a positive effect on the CR phenomenon. In the coupled neuronal network, however, the signal transmission performance of chemical synapses is better than that of electrical synapses. The time delay can determine the trend of the system response, and the multiple chaotic resonances phenomenon is observed upon fine-tuning the time delay length. Both sub-harmonic chaotic resonance and chaotic anti-resonance appear when the STS period and time delay are locked. In chained networks, the signal transmission performance between electrical synapses attenuates continuously. Conversely, the performance between chemical synapses reaches a steady state.

3.
Cogn Neurodyn ; 14(4): 569-578, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32655717

RESUMO

Ionic channel blockage and multiple oscillatory signals play an important role in the dynamical response of pulse sequences. The effects of ionic channel blockage and ionic channel noise on the discharge behaviors are studied in Hodgkin-Huxley neuronal model with multiple oscillatory signals. It is found that bifurcation points of spontaneous discharge are altered through tuning the amplitude of multiple oscillatory signals, and the discharge cycle is changed by increasing the frequency of multiple oscillatory signals. The effects of ionic channel blockage on neural discharge behaviors indicate that the neural excitability can be suppressed by the sodium channel blockage, however, the neural excitability can be reversed by the potassium channel blockage. There is an optimal blockage ratio of potassium channel at which the electrical activity is the most regular, while the order of neural spike is disrupted by the sodium channel blockage. In addition, the frequency of spike discharge is accelerated by increasing the ionic channel noise, the firing of neuron becomes more stable if the ionic channel noise is appropriately reduced. Our results might provide new insights into the effects of ionic channel blockages, multiple oscillatory signals, and ionic channel noises on neural discharge behaviors.

4.
Cancer Manag Res ; 12: 4209-4216, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32581592

RESUMO

INTRODUCTION: The incidence of cervical squamous cell carcinoma (CSCC) has expanded in recent years. However, the function of long non-coding RNA (lncRNA) MAGI2-AS3 in the occurrence and progression of CSCC remains unclear. Therefore, the role of lncRNA MAGI2-AS3 in cervical squamous cell carcinoma (CSCC) was investigated in our study. METHODS: We used qRT-PCR analysis to identify the level of MAGI2-AS3 mRNA expression in CSCC clinical samples and cell lines. We investigated cell migration and invasion of CSCC cells transfected with MAGI2-AS3, miR-233 mimic, or EPB41L3 with transwell assays. Bioinformatics analysis and a luciferase reporter assay were employed to predict the interaction between MAGI2-AS3 and miR-233. RESULTS: We found that MAGI2-AS3 and EPB41L3 were both downregulated in CSCC and the expression of this two was positively correlated. Bioinformatics analysis showed that MAGI2-AS3 might bind to miR-233, which could directly target EPB41L3. In CSCC cells, overexpression of MAGI2-AS3 led to upregulated, while overexpression of miRNA-233 led to downregulated expression of EPB41L3. However, MAGI2-AS3 and miR-233 did not affect the expression of each other. In addition, overexpression of MAGI2-AS3 and EPB41L3 led to inhibited cancer cell invasion and migration, while overexpression of miR-233 played an opposite role and attenuated the effects of overexpressing MAGI2-AS3. CONCLUSION: MAGI2-AS3 may sponge miR-233 to upregulate EPB41L3, thereby inhibiting CSCC cell invasion and migration.

5.
Hum Cell ; 32(4): 515-521, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31388923

RESUMO

This study aimed to investigate the role of lncRNA terminal differentiation-induced ncRNA (TINCR) in cervical squamous cell carcinoma (CSCC). By informatics analysis, we found that miR-302 may bind TINCR. Expression analysis showed that miR-302 was downregulated, while TINCR was upregulated in CSCC. Correlation analysis showed that they were not significantly correlated. In CSCC cells, miR-302 and TINCR failed to affect the expression of each other. However, miR-302 overexpression led to downregulated and TINCR overexpression led to upregulated cyclin D1 expression in CSCC cells. Interestingly, overexpression of cyclin D1 led to upregulated miR-302 and TINCR. Cell proliferation analysis showed that TINCR and cyclin D1 overexpression led to increased, while miR-302 overexpression led to decreased rate of cell proliferation. Moreover, miR-302 overexpression reduced the effects of TINCR overexpression. Therefore, TINCR sponges miR-302 to upregulate cyclin D1 in CSCC, thereby promoting cell proliferation.


Assuntos
Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Ciclina D1/genética , Ciclina D1/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , RNA Longo não Codificante/fisiologia , Regulação para Cima/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia , Adulto , Idoso , Proliferação de Células/genética , Feminino , Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Ligação Proteica , RNA Longo não Codificante/metabolismo
6.
Med Sci Monit ; 23: 1146-1155, 2017 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-28259893

RESUMO

BACKGROUND Colorectal adenocarcinoma is the second leading cause of cancer-related death in the world. The stage of the disease is related to the survival of the patient, and in early phases surgery is the main modality of treatment. The main aim of modern medicinal chemistry is to synthesize small molecules via drug designing, especially by targeting tumor cells. MATERIAL AND METHODS A new series of 19 compounds containing benzothiazole and thiazole were designed. Molecular docking studies were performed on the designed series of molecules. Compounds showing good binding affinity towards the EGFR receptor were selected for synthetic studies. Characterization of the synthesized compounds was done by FTIR, 1HNMR, Mass and C, H, N, analysis. RESULTS The anticancer evaluation of the synthesized compounds was done at NIC, USA at a single dose against colon cancer cell lines HCT 116, HCT15, and HC 29. The active compounds were further evaluated for the 5-dose testing. Compounds were designed by using docking analysis. To ascertain the interaction of EGFR tyrosine kinase binding, energy calculation was used. CONCLUSIONS The results of the present study indicate that the designed compounds show good activity against colon cancer cell lines, which may be further studied to design new potential molecules.


Assuntos
Neoplasias do Colo/patologia , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Trifosfato de Adenosina , Antineoplásicos/química , Antineoplásicos/farmacologia , Benzotiazóis/química , Benzotiazóis/farmacologia , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Humanos , Ligação de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Simulação de Acoplamento Molecular
7.
Anal Chim Acta ; 587(1): 104-9, 2007 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-17386760

RESUMO

A Ru(bpy)(3)(2+)-based electrochemiluminescence (ECL) detection coupled with capillary electrophoresis (CE) has been established for the determination of sinomenine for the first time. Optimum separation was achieved with a fused-silica capillary column (50 cm x 25 microm i.d.) and a background electrolyte of 50 mM sodium phosphate (pH 5.0) at a separation voltage of 15 kV. The content of sinomenine was detected by ECL at the detection voltage of 1.15 V (versus Ag/AgCl) with 5 mM Ru(bpy)(3)(2+) in 75 mM phosphate solution (pH 8.0) when a chemically modified platinum electrode by europium(III)-doped prussian blue analogue (Eu-PB) was used as a working electrode. Under the optimized conditions, the ECL intensity was in proportion to sinomenine concentration in the range from 0.01 to 1.0 microg mL(-1) with a detection limit of 2.0 ng mL(-1) (3sigma). The relative standard derivations of migration time and ECL intensity were 0.93 and 1.11%, respectively. The level of sinomenine in Sinomenium acutum Rehd. et Wils was easily determined with recoveries between 98.6 and 102.7%.


Assuntos
Eletroquímica/métodos , Eletroforese Capilar/métodos , Morfinanos/análise , Calibragem , Eletrodos , Eletrólitos/química , Ferrocianetos/farmacologia , Concentração de Íons de Hidrogênio , Luminescência , Medicina Tradicional Chinesa/métodos , Fosfatos/farmacologia , Extratos Vegetais , Platina/química , Rubídio/química , Solventes/química
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